This document relates to information processing, including encoding and decoding in information and communications systems.
Noise on a communications channel, can cause the signal received from the communications channel to be different from the original signal transmitted or stored on the channel. Channel coding, or equivalently, error correction coding, relates to techniques for increasing the probability that a receiver in a communications systems will be able to correctly detect the composition of the transmitted data stream. Increasing such a probability can be accomplished by encoding a signal to add redundancy before transmittion or storage. This redundancy increases the likelihood that the receiver will be able to correctly decode the encoded signal and recover the original data.